#!/bin/sh
# Copyright 2021 Stan Grishin (stangri@melmac.ca)
# shellcheck disable=SC1091,SC2039,SC2034,SC3043
readonly PKG_VERSION='dev-test'
readonly PROG=/usr/sbin/nebula
readonly packageName='nebula-proto'

[ -x "$PROG" ] || { log "Main nebula executable '/usr/sbin/nebula' not found"; exit 1; }

[ -n "$INCLUDE_ONLY" ] || {
	. /lib/functions.sh
	. /lib/functions/network.sh
	. ../netifd-proto.sh
	init_proto "$@"
}

log() { logger -t "$packageName" "$*"; }
# https://gist.github.com/pkuczynski/8665367
# shellcheck disable=SC2086,SC2155
parse_yaml() {
	local prefix=$2
	local s='[[:space:]]*' w='[a-zA-Z0-9_-]*' fs="$(echo @|tr @ '\034'|tr -d '\015')"
	sed -ne "s|^\($s\)\($w\)$s:$s\"\(.*\)\"$s\$|\1$fs\2$fs\3|p" \
	-e "s|^\($s\)\($w\)$s:$s\(.*\)$s\$|\1$fs\2$fs\3|p" "$1" |
	awk "-F$fs" '{
		indent = length($1)/2;
		vname[indent] = $2;
		for (i in vname) {if (i > indent) {delete vname[i]}}
		if (length($3) > 0) {
			vn=""; for (i=0; i<indent; i++) {vn=(vn)(vname[i])("_")}
			printf("%s%s%s=\"%s\"\n", "'$prefix'", vn, $2, $3);
		}
	}'
}

proto_nebula_init_config() {
	available=1
	no_device=1
	proto_config_add_string "config_file"
}

proto_nebula_setup() {
	local interface="$1" config_file address addresses
	local yaml_listen_host yaml_listen_port yaml_tun_dev

	config_load network
	config_get config_file "${interface}" "config_file"
	proto_init_update "${interface}" 1

	[ -s "$config_file" ] || { log "Config file not found or empty!"; return 1; }
	eval "$(parse_yaml "$config_file" "yaml_")"
	[ "$yaml_tun_dev" = "$interface" ] || { log "Tunnel device in config file (${yaml_tun_dev}) doesn't match interface name (${interface})!"; return 1; }

	log "Setting up ${interface} from $(basename "$config_file")."
	proto_run_command "$interface" "$PROG" -config "$config_file"
	proto_add_data
	json_add_array firewall
		json_add_object ""
		json_add_string type rule
		json_add_string name "$interface"
		json_add_string src "*"
		json_add_string dest_ip "${yaml_listen_host:-0.0.0.0}"
		json_add_string dest_port "${yaml_listen_port:-4242}"
		json_add_string proto udp
		json_add_string target ACCEPT
		json_close_object
	json_close_array
	proto_close_data
	addresses="$(ip -4 a list dev "$interface" 2>/dev/null | grep inet | awk '{print $2}' | awk -F "/" '{print $1}')"
	log "Running ${interface} from $(basename "$config_file") with addresses: ${addresses}."
	for address in ${addresses}; do
		case "${address}" in
			*:*/*)
				proto_add_ipv6_address "${address%%/*}" "${address##*/}"
				;;
			*.*/*)
				proto_add_ipv4_address "${address%%/*}" "${address##*/}"
				;;
			*:*)
				proto_add_ipv6_address "${address%%/*}" "128"
				;;
			*.*)
				proto_add_ipv4_address "${address%%/*}" "32"
				;;
		esac
	done

	proto_send_update "$interface"
}

proto_nebula_teardown() {
	local interface="$1"
	proto_kill_command "${interface}"
	log "Killed interface ${interface}."
}

[ -n "$INCLUDE_ONLY" ] || {
	add_protocol nebula
}
